I must admit to not being a fan of the approach Bryston have taken here - its very limited.
I can see the point of the simplicity of a hard drive - not having to network etc., but this is wholly contradicted by the need to have a network connection to be able to control the device from a wifi device such as those from Apple (which, of course, adds another minimum of £200 to the price of the BDP-1). So for remote control you need a network anyway. You'll also need to wait for the BDP-1 to scan your music collection on the hard drive everytime you plug it back in again after you've added new music to the drive - that might turn out to be rather tedious.
Remember that, with a DAC, this device is at a similar price point to the Linn Akurate DS in the UK. Something to ponder.
I'm open minded enough to think that there's a place out there for this player, but it will be interesting to see if it takes off.
One last thought - the Squeezebox Touch can technically provide a very similar (if not identical) function to the BDP-1 - in addition to all the other stuff it does such as having a merely adequate built-in DAC - for 10% of the price. And it has a much nicer screen and interface.
Anyone out there up for comparing a Touch playing from a USB stick into a decent external DAC and the same content through the BDP-1 into the same external DAC?